What a bellows is
A bellows is a flexible, accordion-style, light-tight tube that sits between the lens and the film or sensor. Because it can lengthen or shorten, it changes the distance between the lens and the image plane. That distance determines both where the lens focuses and how large the subject appears.
The bellows keeps stray light out while letting that distance vary smoothly, which a rigid tube cannot do.
Why old cameras had bellows
Bellows served two main purposes in older cameras.
- Portability. Folding cameras collapsed so the lens and bellows folded into a compact body. This made medium-format and larger cameras easier to carry and is why many early roll-film cameras looked the way they did.
- Focusing and movements. View cameras and field cameras moved the lens in relation to the film. Racking the bellows in or out focused the lens. Many of these cameras also allowed the front and rear standards to shift or tilt, which can correct converging lines or adjust the plane of focus.
Before compact helical focusing lenses became common, a flexible extension was a practical solution to both needs.
Are bellows still used today?
Yes, though mostly in specialised areas.
- Large-format and view cameras still use bellows, and film and digital users keep them for movements and image quality.
- Macro bellows units attach between a camera body and a lens to reach high magnification, including beyond life size.
- Copy and repro stands use bellows for flat artwork and document copying.
- Vintage folding cameras are used by collectors and film enthusiasts.
For everyday macro work, a dedicated macro lens or extension tubes are more convenient, but a bellows can offer greater and continuously adjustable extension.
How bellows give magnification
Magnification depends on how far the lens sits from the sensor. A useful approximation: for a lens focused at infinity, the lens-to-sensor distance equals the focal length. As you extend it, magnification increases roughly by the added extension divided by the focal length. For example, adding extension equal to the focal length gives about 1:1 magnification.
That is why short focal lengths are popular on macro bellows: they reach high magnification with less extension, though they also sit very close to the subject. Reversing a lens can help optical quality at high magnifications, because many lenses are designed for a distant subject and a nearer sensor.
Exposure and settings with a bellows
Extending the lens spreads the light over a longer path, so the effective aperture becomes smaller than the number marked on the lens. A common estimate is effective f-number = marked f-number multiplied by (1 plus magnification). At 1:1 that means roughly two stops of light are lost.
- With through-the-lens metering on a modern camera, the meter usually accounts for this, but check the result.
- With a manual-only setup or a separate meter, apply the correction yourself.
- Because the effective aperture is small, diffraction can soften the image, and you may need strong light or long exposures.
Depth of field is extremely thin at high magnification, so many photographers combine a bellows with focus stacking. Plan your light accordingly; see the macro photography lighting setup for options, and the jewellery photography settings guide for a stacking workflow.
Bellows vs extension tubes
| Bellows | Extension tubes | |
|---|---|---|
| Extension | Continuously adjustable | Fixed steps, can be stacked |
| Portability | Bulkier and more delicate | Small and rugged |
| Electronics | Often none, so manual aperture and focus | Some pass electronic signals |
| Typical use | High magnification, studio | Quick close-up work, travel |
Tubes are the easier option for most. Bellows suit a tripod-based studio where you want precise control.
Using a macro bellows step by step
- Mount the bellows on a focusing rail or a sturdy tripod. Stability matters more than anything else.
- Attach the camera to the rear standard and the lens to the front.
- Set manual mode, base ISO and a mid-range aperture, remembering the effective aperture is smaller.
- Choose magnification by extending the bellows, then focus by moving the entire assembly with the rail rather than turning the focus ring.
- Use strong, diffused light and a remote release or timer.
- Take test frames, check sharpness at 100%, and adjust exposure.
Buying older gear: what to check
- Look for pinholes or cracks in the bellows by holding it up to a bright light in a dark room.
- Check that the standards slide smoothly and lock firmly.
- Confirm the lens mount and any adapters are compatible with your camera.
- Check whether the aperture is controlled by the lens or by a coupling cable.
FAQ
Why did old cameras have bellows?
For compact folding designs and for focusing with adjustable lens-to-film distance, often with the ability to tilt or shift the lens.
What are the basic parts of a camera?
The usual list includes the body, lens, aperture, shutter, viewfinder, and the film or sensor, along with controls such as a mode dial or shutter release. Different sources count them differently, and our guide to camera components explains what each one does.
What are some different types of cameras?
Common types include view cameras, folding cameras, rangefinders, SLRs, DSLRs, mirrorless cameras, compact cameras, medium-format cameras and instant cameras.